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Using data read from port COM

Hi,

I have a question concerning some problems that I have in my study project.

My goal is to create a device that measures signal (PPG) and sends it via bluetooth to my laptop.

I have estabilished transmision, and I read data from my COM port, but I am not able to make it a signal, so that I could use blocks like filtration, or peak detection.

I think of connecting recieved data to DAQ assistant, but I don't know is it possible, and how to do this.

I have just started a LabView adventure, so I will appreciate any help!

Regards!

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Message 1 of 6
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Hi Lems,

I have inserted the image of the front panel and the block diagram for plotting the ECG using the of the PPG sensor. I have used The VISA to get the serial data and then plot it using a Strip chart.

The data from the serial port is converted from decimal string to number. From here you can manipulate the ECG using any blocks like filtration, or peak detection. You cannot use the DAQ for this purpose since DAQ does not have serial ports.

thank you

with kind Regards,

Mohamed Shakir

LabVIEW CLAD Developer

Qatar

front.jpgBlock.jpgconfigure serial port.jpg

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Message 2 of 6
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Hi Lems,

I have inserted the image of the front panel and the block diagram for plotting the ECG using the of the PPG sensor. I have used The VISA to get the serial data and then plot it using a Strip chart.

The data from the serial port is converted from decimal string to number. From here you can manipulate the ECG using any blocks like filtration, or peak detection. You cannot use the DAQ for this purpose since DAQ does not have serial ports.

thank you

with kind Regards,

Mohamed Shakir

LabVIEW CLAD Developer

Qatar

front.jpgBlock.jpgconfigure serial port.jpg

Message 3 of 6
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Thank you very much, for your fas help!

I'll try to change something in my app, and then I'll write in case of other problems.

Thank you one more time!

Kindest regards

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And now I have this stupid problem, that I am not able to overcome but I believe, that solution is simple.

I have this two-byte data, because of having 10-bit ADC. So I was converting my string read from VISA to unsigned byte array in order to extract components and join them into one value.

I've tried to do the reading the way your picture shows, but I am not sure, how i should format my datapacket so that it would work.

Regards, and thanks!

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Message 5 of 6
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Ok,

I've dealt with transmissiom problem, now I'm sending data as decimal string with a coma as delimiter.

So I'm using spreadsheet string to array converter to get my data and plot it.

But I get strange modulated like signal:

host.jpg

It should be the positive part of sine, but not so spike-like.

Signal frequency is only 2Hz, baud rate is 9600, sampling frequency of ADC is way over 250Hz (don't remember exact value), so I shouldn't have problems with getting this signal right. Yet I have.

Here's picture of what I've done:

app.jpg

I didn't make any controls for visa port, beacuse I have everything like in default setup.

It doesn't matter if I use decimal string to number, nor spreadsheet string to array.

If anyone has a clue and a tip of how to get it rigth, I would be gratefull

Kind regards!

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Message 6 of 6
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